The present invention relates generally to fluid filters and conditioners, and more particularly to filters and conditioners for liquid coolant.
In certain fluid systems, for example in cooling systems for internal combustion engines, a liquid coolant degrades over time as it recirculates through the system. It can be necessary or desirable to recharge the coolant by releasing inhibitors into the flow. This is done by locating a recharge assembly, including a housing and a replaceable recharge canister, in the liquid line.
It is also known to add a filter assembly, including a housing and replaceable filter element, to the cooling system in order to remove particulates such as rust, scale and dirt. Such a filter assembly, however, requires additional space in the engine compartment in addition to the recharge assembly. Both the filter element and recharge canister also must be separately accessed from their respective housings and replaced when they become spent.
The amount of space available for the recharge assembly and filter assembly is limited. So too is the time and effort available to access both assemblies for replacement of the recharge canister and filter element. It is believed that it would be advantageous to combine the recharge assembly and filter assembly into an integral, compact assembly. It is also believed it would be advantageous to provide such an assembly where the filter element and recharge canister are combined into a cartridge, which can be easily accessed and removed as a single component when spent. It is further believed advantageous that such a recharge and filter assembly be robust, dependable and low in cost.
The present invention provides a novel and unique recharge and filter assembly which combines a recharge assembly and filter assembly into an integral, compact assembly. The recharge and filter assembly includes a replaceable recharge and filter cartridge, which can be easily accessed and removed as a single component when spent. The assembly has components which are relatively easy to manufacture, are low in manufacturing and maintenance costs, and have a long life. The recharge and filter assembly is particularly suited to be located within the liquid line in a cooling system of an internal combustion engine to recharge coolant in the system, as well as to remove particulate matter and other contaminants.
According to the present invention, the recharge and filter assembly includes a housing having a cylindrical canister with an inlet and outlet at a closed end of the canister, and a cover which can be removably screwed onto an open end of the canister. A short standpipe extends centrally within the housing from the closed end towards the open end. The standpipe includes an internal passage fluidly connected to the housing outlet.
The recharge and filter cartridge is received within the canister of the housing, and includes a filter element portion and a recharge canister portion. The filter element portion has a ring-shaped media and upper and lower end caps. A peripheral flow passage is defined between the radially outer surface of the filter media and the housing canister. A cylindrical imperforate weir supports the inner surface of the filter element, and extends along the filter element from the lower end towards the upper end. A flow passage is provided between the upper end of the weir and the upper end cap.
The lower end cap of the filter element includes an annular body portion fixed to the lower end of the filter media, and defining a central opening. An annular resilient seal bounds the central opening and seals against the central standpipe when the element is located within the housing. The housing canister includes an annular radially-inward projecting shoulder which supports the lower surface of the lower end cap toward the closed end of the housing. The lower end cap includes a series of ribs on its lower surface, which are supported on the annular shoulder and define flow paths between the lower end cap and the peripheral flow passage.
The upper end cap of the filter element also includes an annular body portion fixed to the upper end of the filter media. The upper end cap includes a radially outward projecting annular flange portion with a radially outward-facing groove which receives an annular resilient O-ring. When the filter element is located in the housing, the O-ring seals against a gland proximate the open end of the canister to prevent fluid passing into the area between the upper end cap and the cover. An annular channel, facing axially upward from the upper end cap, is provided in the annular flange portion between the annular body portion and the seal. An outer annular support ring projecting downward from the cover is received within the annular channel and supports the upper end cap during operation.
The upper end cap further includes a well area extending radially inward from the annular body portion. A series of latching fingers extend upwardly from the well area, and cooperate with a downwardly-extending mating ring from the cover to couple the recharge and filter cartridge to the cover. The cooperating latching fingers and mating ring facilitate removing and replacing the recharge and filter cartridge when spent. The mating ring on the cover also contacts the well area in the upper end cap to support the upper end cap during operation.
The recharge canister portion of the cartridge is supported internally of the filter element. An annular flow passage is provided between the recharge canister and the cylindrical weir supporting the filter media. The recharge canister includes a cylindrical body portion enclosing inhibitor material, and annular side walls projecting axially from the upper and lower ends of the body portion. The upper side wall is sealed to the upper end of the weir, and includes a series of flow openings, preferably equally spaced around the side wall. The upper side wall of the recharge canister is supported on a series of tabs formed integral with the upper end cap. The tabs on the upper end cap support the upper side wall at a location spaced apart from the upper end cap such that flow openings are provided between each of the tabs on the upper end cap. The lower side wall of the canister is supported on a series of tabs formed integral with the lower end cap. The tabs on the lower end cap similarly support the lower side wall of the recharge canister such that flow passages are provided between the tabs on the lower end cap.
The fluid flow to be recharged and filtered enters through the housing inlet and passes through the flow paths defined between the ribs on the lower end cap into the peripheral flow passage between the filter element and canister. The flow then passes radially inward through the filter media, where the flow is filtered, and then passes through the flow passage defined between the upper end cap and the upper end of the weir. The liquid then comes into contact with the inhibitor at the upper end of the recharge canister, where the liquid is recharged. The recharged liquid then flows through the flow openings in the upper annular side wall of the recharge canister, and then downwardly through the flow passage defined between the recharge canister and the weir. The flow then passes through the passages defined between the tabs on the lower end cap, and enters the central standpipe, where the flow then passes to the housing outlet.
Sensors mounted to the housing monitor outlet fluid temperature and the integrity of the recharge canister, to confirm when the cartridge needs to be replaced. To replace the recharge and filter cartridge, the cover is removed from the housing canister. The recharge and filter cartridge is removed with the cover because of the cooperating mating ring on the housing cover and the latching fingers on the upper end cap. The cartridge can be easily uncoupled from the cover and thrown away, and a new cartridge installed in the housing.
Thus, as described above, the present invention provides an integral, compact recharge and filter assembly. The recharge and filter assembly includes a recharge and filter cartridge that is easily accessed and removed from the housing as a single component when spent. The robust, dependable assembly also is relatively easy to manufacture, has low manufacturing and maintenance costs, and has a long life. The assembly can be located in a liquid line of the cooling system to recharge liquid coolant and filter particulates and other contaminants.
Further features of the present invention will become apparent to those skilled in the art upon reviewing the following specification and attached drawings.